BACKGROUND OF THE BENCHMARKING SYSTEM

In 1991, the IAEA initiated a Technical Assistance Regional Project on Advice on Waste Management of WWER type reactors. The overall project objective was to improve the safety, reliability and performance of radioactive waste management systems at NPPs with WWERs. The design concept for waste management at WWERs involved the storage of untreated waste at NPP sites followed by the treatment, conditioning and disposal of accumulated waste during the decommissioning stage. This resulted in the accumulation of large amounts of radioactive waste stored at NPP sites and increased the risk of radiological incidents and contamination of the environment. There was, therefore, a need in countries operating WWER-type reactors to prepare and realize a new waste management strategy covering all long term aspects of waste management. The project was met with a great interest and all countries operating WWER NPPs at that time (Bulgaria, Czech Republic, Finland, Hungary, the Russian Federation, Slovakia and Ukraine) took part in the project from the very beginning.

The project mentioned above had two phases and lasted for four years. The first phase, that started in May 1991 and finished in December 1992, included identification of common problems and the provision of general recommendations and conclusions for the operators regarding radioactive waste management. At this stage the project also served to reestablish broken contacts between WWER operators after disintegration of the Council for Mutual Economic Assistance (CMEA) and to provide a unified force that would coordinate further activities in the NPP waste management area.

During the execution of the first phase of the project it was concluded that most countries operating WWER reactors had experienced serious problems with radioactive waste management. These problems were technical in nature and they manifested in:

• Concerns over differences in a waste management philosophy between WWER and other PWR design NPPs;

• Perceived higher waste generation rates at WWER plants than at their Western counterparts;

• Lack of public confidence that waste management at WWER plants could meet safety and reliability standards that were imposed and followed by the power plants operated in Western countries.

Most of these claims were based on qualitative statements which did not take into consideration differences in plant operating practices. Furthermore, these claims were not supported by any quantitative analysis that objectively compared waste generation rates at Western NPPs with the quantities of waste that were generated at plants using WWER-type reactors.

The results and the recommendations of the first phase of the project were published in 1993 as IAEA-TECDOC-705 Radioactive Waste Management of WWER-type Reactors [10], in which the following were pointed out:

(1) The introduction of an effective waste management system at NPPs and the further improvement of both operational and long term safety requires the application of a system engineering approach to all elements of the national waste management systems;

(2) Waste management practices currently applied at WWER NPPs could be substantially improved through administrative measures.

Consequently, based on the issues raised and recommendations made during the first stage, the next phase of the project was initiated and ran from February 1993 to mid-1995, this phase consisted of two tasks:

Task A — Evaluation of the existing NPP radioactive waste management infrastructure in participating countries and comparison with those prevailing in the selected industrialized European countries (France, Spain and the United Kingdom);

Task B — Comparative evaluation of the radioactive waste management systems of NPPs with WWER-type reactors.

The route selected to achieve the objective of Task A involved the preparation of a questionnaire which was completed by representatives of each of the participating countries.

In 1994, the results of the Task A study were published in the form of working material entitled Legal Frameworks and Regulatory Structures for Radioactive Waste Management in Selected Countries of Eastern and Central Europe.

The objective of Task B was to develop an analytical, computerized tool that would allow objective comparison of waste management systems and provide insight to design and operational strengths and weaknesses pertinent to WWER NPPs.

From the beginning it was decided to use to the possible extent the experience and results achieved at the Electric Power Research Institute (ERPI) within the US project entitled Identification of Radioactive Waste Sources and Reduction Techniques and initiated in 1982.

The ERPI project was aimed at establishing a reliable database on radioactive waste management systems at NPPs which could be used for comparative purposes with other NPPs. A standardized assessment methodology to enable a utility to evaluate effectiveness of the radioactive waste system in comparison with other NPPs was developed and utilized. A systematic evaluation methodology developed was used for periods: 1978–1981, 1982–1986 and 1986–1992. The ERPI project helped US NPP operators drastically reduce the quantity of generated waste. Over time that project evolved into a programme that became a part of the

‘waste minimization policy’ for utilities in the USA.

Task B activities were performed during the series of Expert Group meetings and workshops.

A comprehensive and structured project questionnaire, that fully followed the design

requirements of WWER reactors, was developed. In addition, instruction that led potential users, step by step, through required data collection and preparation was presented. And consequently, a comprehensive and detailed WWER Waste Management Database was compiled, containing:

• Waste management policies and technical requirements in participating countries;

• Design data and operating parameters for waste collection, waste processing, and waste conditioning systems;

• Characteristics of each waste stream at the plant (amount, volume, waste form, and chemical and radiochemical composition);

• Liquid discharge limits for each plant.

As a conclusion of Task B, the Expert Group recommended that the IAEA continue activities directed to improve radioactive waste management at WWER NPPs. These activities aimed at implementation of the waste minimization approach in waste management at NPPs by transferring the principles, tools, and organizational requirements of the waste minimization programmes to the WWER operators and aligning their practices to western standards.